93
© Springer Nature Switzerland AG 2020
B. R. Singh et al. (eds.), Climate Impacts on Agricultural and Natural Resource
Sustainability in Africa, https://doi.org/10.1007/978-3-030-37537-9_5
Integrated Soil Fertility Management
Based on Pigeon Pea and Cowpea
Cropping Systems Influences Nitrogen Use
Efficiency, Yields and Quality
of Subsequent Maize on Alfisols in Central
Malawi
Keston O. W. Njira, Ernest Semu, Jerome P. Mrema, and Patson C. Nalivata
Abstract An integrated soil fertility management (ISFM) involving food grain
legumes in predominantly maize systems is becoming popular in southern Africa. A
study on diversified pigeon pea and cowpea cropping systems was conducted on
Alfisols in Lilongwe and Dowa districts of Central Malawi. The objective of the
study was to evaluate the residual effects of legume-legume and legume-cereal intercropping systems involving pigeon pea (PP) and cowpea (CP) when integrated with
inorganic nitroen (N) fertilizer on N mineralization patterns, rotational maize (MZ)
N uptake, maize yield, maize grain crude protein content (grain quality), and nitrogen use efficiency (NUE) in the forfm of partial factor productivity of applied N
(PFP N ). The field experiment was arranged in a split plot design with the previous
legume-based systems (with residues retained) as main plots and the 0, 45, 90 and
120 kg ha
−1
inorganic N rates as sub-plots. Results showed significantly higher
(P < 0.05) NUE in plots that were previously legume-based of 76.5 kg grain kg
−1
N
applied in a previously Sole CP, compared to 39.4 kg grain kg
−1
N applied in a previously Sole MZ, for Lilongwe site and 78.4 kg grain kg
−1
N applied in a preciously
PP + CP intercrop, compared to 40.5 kg grain kg
−1
N applied in a previously Sole
MZ, for Dowa site. Similarly, results from treatments that were previously legumebased consistently showed significantly higher (P < 0.05) maize grain yield increases
by ranges of 30–59% at 0 kg N ha
−1
and 28–42% at 120 kg N ha
−1
fertilizer application rate at the Lilongwe site. Similar trends were observed for the Dowa site, with
the highest grain yield increase of 45% under treatment that was previously PP + CP
intercrops. Maize grain protein significantly (P < 0.05) increased with additions of
K. O. W. Njira (*) · P. C. Nalivata
Crop and Soil Sciences Department, Lilongwe University of Agriculture and Natural
Resources, Lilongwe, Malawi
e-mail: knjira@luanar.ac.mw
E. Semu · J. P. Mrema
Department of Soil and Geological Sciences, Sokoine University of Agriculture,
Morogoro, Tanzania
© Springer Nature Switzerland AG 2020
B. R. Singh et al. (eds.), Climate Impacts on Agricultural and Natural Resource
Sustainability in Africa, https://doi.org/10.1007/978-3-030-37537-9_5
Integrated Soil Fertility Management
Based on Pigeon Pea and Cowpea
Cropping Systems Influences Nitrogen Use
Efficiency, Yields and Quality
of Subsequent Maize on Alfisols in Central
Malawi
Keston O. W. Njira, Ernest Semu, Jerome P. Mrema, and Patson C. Nalivata
Abstract An integrated soil fertility management (ISFM) involving food grain
legumes in predominantly maize systems is becoming popular in southern Africa. A
study on diversified pigeon pea and cowpea cropping systems was conducted on
Alfisols in Lilongwe and Dowa districts of Central Malawi. The objective of the
study was to evaluate the residual effects of legume-legume and legume-cereal intercropping systems involving pigeon pea (PP) and cowpea (CP) when integrated with
inorganic nitroen (N) fertilizer on N mineralization patterns, rotational maize (MZ)
N uptake, maize yield, maize grain crude protein content (grain quality), and nitrogen use efficiency (NUE) in the forfm of partial factor productivity of applied N
(PFP N ). The field experiment was arranged in a split plot design with the previous
legume-based systems (with residues retained) as main plots and the 0, 45, 90 and
120 kg ha
−1
inorganic N rates as sub-plots. Results showed significantly higher
(P < 0.05) NUE in plots that were previously legume-based of 76.5 kg grain kg
−1
N
applied in a previously Sole CP, compared to 39.4 kg grain kg
−1
N applied in a previously Sole MZ, for Lilongwe site and 78.4 kg grain kg
−1
N applied in a preciously
PP + CP intercrop, compared to 40.5 kg grain kg
−1
N applied in a previously Sole
MZ, for Dowa site. Similarly, results from treatments that were previously legumebased consistently showed significantly higher (P < 0.05) maize grain yield increases
by ranges of 30–59% at 0 kg N ha
−1
and 28–42% at 120 kg N ha
−1
fertilizer application rate at the Lilongwe site. Similar trends were observed for the Dowa site, with
the highest grain yield increase of 45% under treatment that was previously PP + CP
intercrops. Maize grain protein significantly (P < 0.05) increased with additions of
K. O. W. Njira (*) · P. C. Nalivata
Crop and Soil Sciences Department, Lilongwe University of Agriculture and Natural
Resources, Lilongwe, Malawi
e-mail: knjira@luanar.ac.mw
E. Semu · J. P. Mrema
Department of Soil and Geological Sciences, Sokoine University of Agriculture,
Morogoro, Tanzania